An optimal real-time short term operation of independent hydro generator company in the open electricity market

Abstract

This paper describes an approach to short-term hydro scheduling and dispatch for the independent hydro generator in the Open Electricity Market (OEM) environment. The paper discusses optimal operation of hydro electric power plants and possible control arrangements in the OEM environment. The algorithm currently used by the Hydro Electric Commission, which operates as an isolated purely hydro system, has been modified to suit any independent hydro generation company. It also provides a different perspective for operation of hydro power plants as part of a hydrothermal system and can also be used for hydro optimisation in hydrothermal systems. The algorithm uses a detailed model of the interconnected hydro system to determine the half-hourly operating schedule based on allocated water releases with the objective of maximising overall return from the market. The plan is revised and updated every five minutes as actual generation requirements and inflows change. This ensures continuous real-time optimisation which is necessary for continuously changing spot prices and inflows into reservoirs. The concept is developed for a decentralised market (as in Australia), but the concept can be used in a centralised dispatched market or centrally planned systems for the optimisation of hydro resources.